This patent document relates to optical devices and techniques for causing optical delays in light.
Optical delay lines are devices that produce desired optical delays in propagation of light and can be operated to adjust signal path delays in light. Optical delay lines can be used in various s applications, including, e.g., optical communication devices/modules, optical sensor devices/systems or other optical instruments. As a specific example, an optical coherence tomography (OCT) system having two interference optical arms for an optical reference beam and an optical sampling beam can implement one or more optical delay lines or devices to cause the relative optical delays between the optical reference and sampling beams.